Beetle L4-1.9L DSL Turbo (ALH) (1998)
A/C Signal: Testing and Inspection
With Manufacturer's Scan Tool
A/C System Signals, Checking
Special tools
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VAG 1551/1552 Scan Tool using VAG 1551/3 Adapter cable
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VAG 1598/22 Test Box (MY 1999)
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VAG 1598/31 Test Box (from MY 2000)
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Fluke 83 multimeter
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VW 1594 Adapter kit
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Wiring diagram
Checking requirements
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A/C function OK
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No malfunctions stored in DTC memory. Refer to "Displaying and Reading Trouble Codes/With Manufacturers Scan Tool/DTC Memory
Checking and Erasing", See: Testing and Inspection
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Vehicle temperature: +15 °C (59 °F) minimum
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A/C system switched ON
A/C compressor shut-off, checking
The A/C control head signals the Engine Control Module that the A/C compressor will be switched ON via the A/C compressor signal.
Using the same wiring, the A/C compressor is switched OFF by the ECM under the following circumstances:
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Hard acceleration from low speed
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Engine is running under an emergency program
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Engine Coolant Temperature exceeds +120 °C (248 °F)
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During every engine start for approx. 6 seconds.
Checking
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Connect VAG 1551/1552 Scan Tool. Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks", See: Testing and Inspection
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Start engine and let idle.
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Press 0 and 1 buttons to select Address word 01: "Engine electronics"
Display will appear as shown (example only)
038906018M 1.9l R4 EDC 00AG 1813
->
Coding 0001
WSC XXXX
-
Press button. Display will appear as shown
Rapid data transfer
HELP
Select function XX
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Press 0 and 3 buttons to select Function 03: "Output Diagnostic Test Mode".
Display will appear as shown
Rapid data transfer
Q
03 Output Diagnostic Test Mode (DTM)
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Press Q button to enter input.
Display will appear as shown
Output Diagnostic Test Mode (DTM)
->
Cold Start injector N108
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Press -> button.
Display will appear as shown
Output Diagnostic Test Mode (DTM)
->
EGR valve N18